Apparatus for screening cytological specimens

ABSTRACT

A slide specimen of exfoliated cells is prepared in the usual manner for microscopic optical examination of a Papanicloaou Test, up to the point of staining. At this stage, instead of the ordinary stains, a stain containing a radioisotope is used. The slide with the radioisotope-bearing stain is thereupon passed through a radiation counter which gives an indication of the amount of radiation the slide emits, which indicates the amount of radioactive stain absorbed by the specimen. This relative absorption amount indicates the differential staining of the cellular material and forms the equivalent electronic differentiation of the specimens to the standard Papanicolaou optical differentiation as viewed through the microscope. In this way, the automatic radiation counter is used to substitute for the human element in the microscopic evaluation of the specimens.

United States Patent [1 1 Caiola APPARATUS FOR SCREENING CYTOLOGICALSPECIMENS Inventor: Leonard Caiola, Ridgewood, NJ.

Information Utilization Corporation, New York, N.Y.

Filed: July 22, 1971 Appl. No.: 165,117

Related U.S. Application Data Division of Ser. No. 836,768, June 26,1969, Pat. No. 3,678,148.

Assignee:

U.S. Cl 250/303, 250/304, 424/1 Int. Cl. G2lh 5/02 Field of Search250/71 T, 71 G, 83.3 UV, 250/106 SC, 43.5 MR, 83 SA, 303, 304; 424/1OTHER PUBLICATIONS Protein Synthesis and RNA Synthesis During MitosisApr. 2, 1974.

in Animal Cells, by Konrad, C. G., from Journal of Cell Biology, Vol.19, 1963, pgs. 267-277.

[5 7] ABSTRACT A slide specimen of exfoliated cells is prepared in theusual manner for microscopic optical examination of a Papanicloaou Test,up to the point of staining. At this stage, instead of the ordinarystains, a stain containing a radioisotope is used. The slide with theradioisotopebean'ng stain is thereupon passed through a radiationcounter which gives an indication of the amount of radiation the slideemits, which indicates the amount of radioactive stain absorbed by thespecimen. This relative absorption amount indicates the differentialstaining of the cellular material and forms the equivalent electronicdifferentiation of the specimens to the standard Papanicolaou opticaldifferentiation as viewed through the microscope. in this way, theautomatic radiation counter is used to substitute for the human elementin the microscopic evaluation of the specimens.

9 Claims, 2 Drawing Figures SPECIMEN IN SUSPENSION I7 l PREPARATION cOULTER czmmrucr a summs COUNTER b3 SPECIMEN FIXED 0N SLIDE LOWBACKGROUND RADIATION COUNTER rum. uromvzs mscmvr D* FINAL posmvtscnrsumc DEVICE a SUSPICIOUS- ir A iA' L r om BANK olThlalT POSATIVE QALL DATA SU SPICIOUS 1 APPARATUS FOR SCREENING CYTOLOGICAL SPECIMENSThis application is a division of US. Pat. application Ser. No. 836,768,filed June 26, 1969, now US Pat. No. 3,678,148.

The present invention relates to the examination of cellular specimensby means of an automatic electronic device instead of manually by amicroscope.

The Papanicolaou Test is well established as a universal medical methodfor the diagnosis of cancer from all mucous cavities of the human body,such as cervical and vaginal cancer in women, and in lung, stomach, andrectal examinations in both sexes. This test is particularly notable inmedicine for its ability to indicate cancer in its earliest stages whenit is most subject to treatment and cure.

For this reason, the Pap Test (as the Papanicolaou Test is known) isinvaluable as a routine check against the presence of cancer. However,since the test is now carried out by trained cyto-technicians seated atmicroscopes, it therefore involves a certain extended amount of time forthe scanning of slides. On the average, the minimum time required, asdetermined by the statistics of the majority of cytologicallaboratories, is fifteen minutes. However, since a degree of humansubjective judgement is involved in such a reading, the number of slidesa single cyto-technician can read is sharply reduced by eye-strain,brain fatigue, and other subjective obstacles to sustained microscopicexamination. None of these obstacles apply to an electronic radiationdetection mechanism, so that the use of such devices decidedly increasesthe number of slides that can be scanned by automatic machinery. Theimportance of this phase of the Pap Testis that it is highly desirableto make this a routine test of all adults, and so the problem of apopulation ratio against the number of cytotechnicians available forsuch testing is of crucial significance to the medical world.

One of the objects of the present invention is to provide anelectromechanical method of evaluating and analyzing slides.

Another object is to conduct such evaluation and analysis in a minimumof time with maximum accuracy.

Another of the objects of the invention is to provide a process for theanalysis of slide specimens for the Pap Test.

According to one aspect of the invention, a test sample of specimen isfurnished in the form of exfoliated cellular material either as a'cellsuspension or slide deposition. When furnished in suspension, it iscounted for cell population by a Coulter/Counter and is thencentrifuged, and the concentrated cell deposit is then spread out orplaced upon a glass slide or slides in equal amounts. The selectivebiological stain containing a ra-.

dioactive element is applied to the slide. The slide is then fixed, andthen conveyed upon a continuous belt to a radioactive responsiveapparatus which is a radiation counter. The counter then registers innumerical form the amount of radiation emitted by each slide. Thedifferential rate of absorption by the cells is the criterion whichdirects the cyto-technician in his optical examination for the presenceof suspicious or positive cancer indications.

The slides are classified according to their radioactive levels suchthat the slides whose levels fall below a certain number are classifiedas negative, those above that range, but below a higher number, areclassified as suspicious, and those at or above ahigher level areclassified as positive. All slides classified suspicious or positive arethen referred to a cyto-technician for careful review by the microscopemethod, and then can be passed on to a Pathologist for confirmation. Inevery case the readings of the radiation counter from all slides arefilled in the storage units of a computer which will store the data andmake complete correlation of all of the findings.

Other objects, advantages and features of the present invention will beapparent from the accompanying description and drawings, which aremerely exemplary.

In the drawings:

FIG. 1 is a schematic diagram; and

FIG. 2 is an elevational view in an enlarged scale and partially insection of one form of holder in the low background radiation counter.

In carrying out the process according to the present invention, theslide specimen for the Pap Test is prepared in a previously knownmanner. Each test sample or specimen is received in the form ofexfoliated cellular material either as a cell suspension or slidedeposition. When furnished in suspension as indicated at 10 in a mannerknown in the art, it is counted for cell population by a Coulter/Counter10A, as manufactured by Coulter Electronics, Inc., Hialeah, Florida, andcan then be automatically conveyed to a centrifuge l 1, centrifuged,with the residue in the form of a cell layer collection beingautomatically deposited onto a microscope slide or slides. Thecentrifuge may be a multiplace cyto-centrifuge such as manufactured bythe Shandon Scientific Co. Ltd., 65 Pound Lane, Willesden, London, GreatBritain. The slide specimen is then automatically stained at aworkstation 12 with a biological stain containing a radioactive materialwhich has the property of attaching to the cells of the specimen. Thecells are thus tagged with a radioactive material. One such stain whichcould .be used is known as methylene blue which has had C added thereto.Others which can be used are C tagged Orange G" and C tagged Eosin.Anotherexample of a stain is hematoxylin tagged with a suitableradioactive material. Other such radioisotopesincluding tritium (H3) maybe used.

Work station 12 may comprise a Shandon-Elliott automatic slidestainingmachine such as manufacuted by said Shandon Scientific Co. Ltdof Willesden, London, Great Britain. The use of automatic slide stainingapparatus speeds up the testing procedure and releases skilledtechnicians from complicated manual slide staining processes.

The staining of slide specimens prior to examination is known in thebio-medical field. However, staining the slide specimen for a Pap Test,so that the cells are tagged with a radioactive material, significantlyfacilitates carrying out the analysis of the slide specimen in a mannerto be presently described.

The stained specimens are then automatically conveyed to a counter suchas one sold under the mark iOmni/Quard 100, a trademark of Tracerlab.The Inway of example, such an instrument can have the followingcharacteristics:

l. Counts Alpha and Beta Radiation 2. Window Thickness 150 micrograms/cm3. Absolute C eff. 35 percent 4. Beta Background 0.5 cpm (1 inch), l cpm(2 inches) The Omni/Guard 100 has an inner detector with an ultra-thinwindow gas flow counter with maximum beta efficiency of 48 percent. Thesurrounding detector is a dome-shaped gas flow counter with a maximumcosmic ray efficiency, serving as the guard counter. The plasticmaterial of the guard counter also serves to shield the inner samplecounter from radiation emitted from the surrounding materials. Itincludes an ultra-thin window l 50 micrograms/cm Because of the verythin window, high intrinsic efficiency and excellent geometry, superbsystem efficiency can be achieved.

The instrument may include a horizontal chain conveyor 14 having anumber of specimen holders or bases 15 thereon upon which a specimen 16can be placed and carried. The sample conveyor positions each samplerelative to a sample changer mechanism located within the housing at 17.it is to be understood that other types of counters or detectors andconveying means can be used.

In order to provide a uniform basis for the comparison of sample, eachsample is retained in the counting position for a uniform period oftime, for example, 12 seconds of exposure. During this time, theradioactive count of the sample is sensed by the counter and may beindicated on a read-out panel 18. The count supplied by the counter willbe a quantitative indication of the radioactive uptake of the cells inthe specimen so as to measure the results of the test.

A predetermined radioactive level may be established so that sampleshaving a count above this level may be designated as positive and sosubject to manual optical examination, and samples having a count belowthis level designated as negative and so spared further examination.Specimens having a count in the region closely adjacent to this levelboth above and below the level may be designated as suspicious and thusbe also subjected to further examination.

The results of the tests of the samples may also be recorded inpunch-card form or programmed so as to constitute an input for acomputer such as a digital computer.v

The slide specimens themselves are initially retained at counter unit13, while data cards corresponding to the specimens are then conveyed toa screening or sorting device at 19 which separates the cardsrepresenting the definitely negative specimens from those representingthe positive and suspicious specimens. The positive and suspiciousspecimens can then be selected for individual examination by skilledtechnicians who are trained to interpret the results of the Pap Test.

The slides in all three categories may be stored for subsequentexamination with the suspicious and positive slides being tagged forreminder so that the persons from whom these specimens were obtained canbe advised of the results and precautionary procedures taken.

By recording to the results of millions of tests on such specimens inthe memory unit of a digital computer, the results can be examined andcorrelated so as to ascertain patterns or trends. Further, technicianswill be able to prognosticate the possibility of cancer occurring inpersons whose tests have been of a particular count. These persons canbe advised that at the present time there is no presence of cancer butthat the tests indicate a predisposition or likelihood of canceroccurring in the future. Thus, such persons can be carefully watched andsubjected to more frequent testing.

The entire apparatus as described above is automatic in nature so thatthe specimens are conveyed automatically between stations on apredetermined time cycle basis. The testing apparatus may be set up inmany different locations but the results of all of these tests can betransmitted to a central computer from which the results of the testsmay be read out as desired.

The present records available to the medical profession of Pap Testshave a rather low order of reliability since the data is subjective innature. The data has depended upon the interpretation of differentspecimens by a number of different individuals having varying degrees ofskill and differing quantities of experience in such analysis work.Different individuals might well disagree on whether or not a particularslide specimen is positive or negative. The present invention providesan objective process of analyzing slide specimens by generating a signalbased on the uptake of a cell. The signal is produced by the radioactivematerial contained in the stain. It is, of course known that theradioactive atom-of and by itself is not necessarily the substance TABLE1 Column 1 Column 2 Column 3 000002 000037 000020 000003 000 l 30 000020000004 000125 000020 000005 000002 000020 Column 1 indicates samplenumber from 1 to 100. V Co lumn 2 indicates the actual electronic countbased on the uptake of the radioactive stain by the cellular tissues onthe slide.

Column 3 shows the time of count and i s read in tenths df'a minute.Thus the above counts werem in two tenths of a minute or 12 seconds.

The diagnosis of these samples is as follows:

2 Inflammatory (non-cancer) 3 Cancer 4 Cancer 5 Negative V WM Thoseskilled in the art will appreciate that different techniques of specimenpreparation and handling can be utilized under this invention. Forexample, cell specimens may be maintained in suspension throughout thecounting, staining and radioactivity measuring steps, with a liquidscintillation counter being suitable for making the radioactivitymeasurements under such conditions.

It should be apparent that variation may be made in the details of theprocess and apparatus without departing from the spirit of theinvention.

What is claimed is:

1. In an apparatus for analyzing specimens for the Pap Test usingexfoliated or tissue biopsy cells, the combination of means forpreparing a specimen and for applying a biological stain containing aradioactive material to the specimen, means for ascertaining theradioactive level of a specimen as a quantitative indication of theuptake of the cells therein of radioactive material, and means forsorting the specimens according to the radioactive levels thereof.

2. In an apparatus as claimed in claim 1 wherein there is a centrifugemeans for acting upon specimens in solution so that a residue isobtained therefrom which residue is fed to the means for preparing thespecimen.

3. In an apparatus as claimed in claim 1 and means for recording theresults of the radioactive levels of specimens.

4. In an apparatus as claimed in claim 1 wherein there is a cellcounter.

5. In an apparatus as claimed in claim 3 wherein said recording meanscomprises a digital computer.

6. In an apparatus as claimed in claim 5, wherein the ascertaining meansincludes means for generating an output signal corresponding to theradioactive level of each of said specimens, and further comprising anoutput readout unit connected to said computer for receiving said outputsignal and for furnishing data to said computer.

7. In an apparatus as claimed in claim 2 and conveyor means fortransferring said specimens between said centrifuge, preparing andstaining means and ascertaining means, and including means fordelivering data corresponding to the radioactive levels of each of saidspecimens to said sorting means.

8. In an apparatus as claimed in claim 6 with said counter having aconveyor upon which said specimens are positioned.

9. In an apparatus as claimed in claim 6 with said means forascertaining the radioactive level having a conveyor for movingspecimens therethrough, a holder for each specimen, and means on saidconveyor for retaining said specimen holders thereon.

1. In an apparatus for analyzing specimens for the Pap Test usingexfoliated or tissue biopsy cells, the combination of means forpreparing a specimen and for applying a biological stain containing aradioactive material to the specimen, means for ascertaining theradioactive level of a specimen as a quantitative indication of theuptake of the cells therein of radioactive material, and means forsorting the specimens according to the radioactive levels thereof.
 2. Inan apparatus as claimed in claim 1 wherein there is a centrifuge meansfor acting upon specimens in solution so that a residue is obtainedtherefrom which residue is fed to the means for preparing the specimen.3. In an apparatus as claimed in claim 1 and means for recording theresults of the radioactive levels of specimens.
 4. In an apparatus asclaimed in claim 1 wherein there is a cell counter.
 5. In an apparatusas claimed in claim 3 wherein said recording means comprises a digitalcomputer.
 6. In an apparatus as claimed in claim 5, wherein theascertaining means includes means for generating an output signalcorresponding to the radioactive level of each of said specimens, andfurther comprising an output readout unit connected to said computer forreceiving said output signal and for furnishing data to said computer.7. In an apparatus as claimed in claim 2 and conveyor means fortransferring said specimens between said centrifuge, preparing andstaining means and ascertaining means, and including means fordelivering data corresponding to the radioactive levels of each of saidspecimens to said sorting means.
 8. In an apparatus as claimed in claim6 with said counter having a conveyor upon which said specimens arepositioned.
 9. In an apparatus as claimed in claim 6 with said means forascertaining the radioactive level having a conveyor for movingspecimens therethrough, a holder for each specimen, and means on saidconveyor for retaining said specimen holders thereon.